Inflammatory Bowel Disease (IBD), comprised primarily of ulcerative colitis (UC) and Crohn's disease (CD), is characterized by a chronic, uncontrolled inflammation of the intestinal mucosa. As many as 1.4 Million people in the United States and 2.2 Million people in Europe currently suffer from IBD, with 30,000 new cases reported each year in the US. Unfortunately, there is no cure for IBD, which necessitates a lifetime of care. There are limited treatment options for CD and UC in the United States, and patients typically receive corticosteroids and immunosuppressive drugs to alleviate symptoms. However, given the toxicity and side effects of these drugs, there is an urgent need for new treatment options for patients with UC and CD. Inflammation of the gastrointestinal tract in IBD is mediated by granulocytes and monocytes. An exciting new therapy for IBD is based on selectively removing these cells from peripheral blood using a strategy known as granulocyte/monocyte apheresis (GMA), with the potential to spare patients from steroids, reduce steroid- dependency, and avoid hospitalization and surgery. Two such GMA devices are approved for use in Japan and Europe, but they operate with varying degrees of specificity and selectivity. This leads to inconsistent treatment efficacy, and increases the risk of unwanted outcomes such as thrombocytopenia or lymphopenia. Furthermore, neither product is approved for use in the United States. Affinergy has discovered a proprietary peptide that binds to monocytes and granulocytes, but does not bind to lymphocytes, erythrocytes, or platelets. We have used this peptide to selectively capture monocytes and granulocytes from whole blood without capturing other cell types. In this Phase 1 application, we will demonstrate proof-of- concept that this peptide can be used to develop a superior GMA device that is both highly selective and highly efficient. In Phase 2, we will test the efficacy of our device using an in viv ulcerative colitis model as we collect data for a submission to the FDA.